Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -4.024 sec. to 13.228 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.99738 ( -0.168319 0.161021 )
Norm@50keV : 2.33748E-03 ( -0.000246744 0.000241177 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.82 using 59 PHA bins.
# Reduced chi-squared = 0.8740 for 57 degrees of freedom
# Null hypothesis probability = 7.388576e-01
Photon flux (15-150 keV) in 17.25 sec: 0.350226 ( -0.028502 0.028518 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.71851e-07 ( -3.64853e-08 3.71824e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.024 sec. to 13.228 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.00632 ( -0.10405 0.627948 )
Epeak [keV] : 30.4214 ( )
Norm@50keV : 2.31060E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.82 using 59 PHA bins.
# Reduced chi-squared = 0.8896 for 56 degrees of freedom
# Null hypothesis probability = 7.065648e-01
Photon flux (15-150 keV) in 17.25 sec: 0.350377 ( -0.028415 0.029231 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.72227e-07 ( -4.32175e-08 3.77587e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.604 sec. to 1.604 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.6755 ( -0.265274 0.253541 )
Norm@50keV : 5.68579E-03 ( -0.000986892 0.000965753 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.62 using 59 PHA bins.
# Reduced chi-squared = 0.9231 for 57 degrees of freedom
# Null hypothesis probability = 6.400871e-01
Photon flux (15-150 keV) in 1 sec: 0.748818 ( -0.115039 0.115059 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.27594e-08 ( -9.52693e-09 9.73052e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.604 sec. to 1.604 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.542794 ( -1.23114 1.87423 )
Epeak [keV] : 55.2864 ( -14.214 -55.2744 )
Norm@50keV : 2.50591E-02 ( -0.0250907 0.275674 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.53 using 59 PHA bins.
# Reduced chi-squared = 0.9023 for 56 degrees of freedom
# Null hypothesis probability = 6.812574e-01
Photon flux (15-150 keV) in 1 sec: 0.724853 ( -0.119305 0.119083 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.73031e-08 ( -1.04274e-08 1.1588e-08 ) ergs/cm2
Time-resolved spectra
